Increased use of synthetic organic polymeric materials commonly referred to as "plastics" in automobile and other industrial production is creating a growing disposal problem. The present method of most common use for disposal of non-metallic components of the product from automobile shredders is by sanitary land fill. Aside from the complete loss of the value of such materials by such disposal, the increasing volume of such scrap and the cost and availability of nearby land fill sites will soon create a major disposal problem. Further, current and potential shortages of some of the monomeric materials used to form such polymeric materials provides a compelling reason to recover and reuse such materials wherever feasible.
One such material used in large quantities is poly (methyl methacrylate), hereinafter called PMMA. A large and increasing quantity of PMMA is a product of automobile shredders which now have as their primary function the recovery of metal from junked automobiles for recycling. The total product of such shredders is commonly subjected to magnetic separation techniques leaving the non-ferrous metals and the plastics in a non-magnetic fraction.
Analysis of a 8.3 lb. sample of the non-magnetic fraction from conventional shredding of an automobile manufactured in the United States, i.e., a sample with density between 1.2 and 1.16 grams/cm.sup.3 and particle size larger than 0.185 inch and smaller than 1.0 inch in diameter revealed the following composition:
Table I ______________________________________ Material % Composition PMMA 30.2 Rubber 7.8 Assorted Plastics 6.2 Fabric (polyvinyl chloride) 1.9 Metal 2.7 Poly (vinyl butyral) 0.6 Glass 0.9 Tar and dirt 49.7 ______________________________________